Efficient synthesis of carborane azo derivatives and their reactivity

Abstract

An iridium(III)-catalyzed C–N-bond-forming direct synthesis of carborane azo derivatives was developed. The reaction of o-carborane monocarboxylate with aryldiazonium salt in the presence of a catalytic amount of [Cp*IrCl₂]₂ and NaOAc in CH₃CN at 80 °C gave the corresponding carborane azo derivative in good yield. A series of cyclometalated iridium/rhodium complexes that contain Cp*M–B (M = Ir, Rh) bonds, and are stabilised by the intramolecular coordination of nitrogen donors, were successfully isolated and structurally characterised.